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Trying to understand the amount of data transfered on wwan0?

I have linux system which is connected to the internet via an lte modem and I am communicating with it via modemManager. So I am having a little bit of difficulty in understanding the number of data bytes consumed.

root@raspberrypi-cm3:~# mmcli -b 0
-------------------------
 Status     | connected : 'yes'
            | suspended : 'no'
            | interfaces: 'wwan0'
            | IP timeout: '20'
 -------------------------
 Properties |       apn: 'myapn'
            |   roaming: 'allowed'
            |   IP type: 'none'
            |      user: 'none'
            |  password: 'none'
            |    number:  'none'
 -------------------------
 Stats      |            Duration: '105060'
            |      Bytes received: '6300'
            |   Bytes transmitted: '6209'

root@raspberrypi-cm3:~# ping -c 1 -s 0 www.opendns.com
8 bytes from ****.****.****.*** seq =0 ttl=50
1 packet transmitted, 1 packet received, 0% packet loss

root@raspberrypi-cm3:~# mmcli -b 0
-------------------------
 Status     | connected : 'yes'
            | suspended : 'no'
            | interfaces: 'wwan0'
            | IP timeout: '20'
 -------------------------
 Properties |       apn: 'myapn'
            |   roaming: 'allowed'
            |   IP type: 'none'
            |      user: 'none'
            |  password: 'none'
            |    number:  'none'
 -------------------------
 Stats      |            Duration: '105090'
            |      Bytes received: '6512'
            |   Bytes transmitted: '6359'

So according to modem manager. I am consuming 150 bytes of data to send a ping to opendns and I am receiving 212 bytes of data?

But how is this possible. I am transmitting 8 bytes and receiving 8 bytes with ICMP header the total will be 16 bytes of data received.

Can someone explain me where are these addition data bytes coming from? Are they simply an over-head when I am communicating with my nameserver? If thats an over-head is there some sort of formula that I can use to calculate the approximate data consumed?

My end goal is just to cross-verify the total data bytes consumed

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Answer

I found my answer by using tcpdump to create a pcap file. Thanks for down voting my question and not providing any answer. For other beginners like me. If you are facing a similar problem. Please use tcpdump this will give you an detailed explanation on packets sent and received by your device.

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